Wilan LIBRA 5800 AP, User Manual

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Glossary
138 Libra 5800 Series User Guide
G
Gain
The ability of a device to amplify a signal. Gain is the ratio of output power divided by input power,
usually expressed in decibels (dB). Gain can also be measured as an absolute value, referenced to
an input signal of one milliwatt (dBm). For antennas, gain measures the ability of an antenna to focus
a signal and is expressed in dBd (half-wave dipole reference) or dBi (isotropic radiator reference).
GPS
Global Positioning System. Wi-LAN Broadband Wireless Access Systems installers may use GPS
devices instead of maps and compasses to locate their unit and orient it toward another station.
I
Ice loading
A problem of antenna operation in cold countries. Ice collects on the antenna and degrades its
performance.
IEEE
Institute of Electrical and Electronics Engineers.
IFIB
Intermediate Frequency Interface Board.
image
An image is a collection of configurations or settings for a particular device. The System Image File
in the Access Point contains a collection of configurations used when the unit is rebooted.
interference
Any signal that tends to hamper the reception of a desired signal. This is equivalent to jamming,
except that interference is not hostile.
IP Address
A number assigned to a network node, domain, or subdivision. An IP Address consists of four
numbers in the form nnn.nnn.nnn.nnn. The first two identify the network and subnetwork, and the last
two identify unique nodes within the network. No two units may possess the same IP within a LAN.
IP Filter
Internet Protocol filtering allows the system administrator to permit only certain IP addresses to
receive or send data using a CPE. This keeps non-subscribers from using the network.
ISM
Industrial, Scientific, and Medical. This is the family of license-exempt radio bands in North America
and some European countries. These are described in part 15.247 of the FCC regulation that defines
the parameters for use of the ISM band in the U.S., including power outputs, spread spectrum, and
noninterference.